US5843090A - Stent delivery device - Google Patents

Abstract

A balloon catheter with a stent delivery device having inner and outer catheters, with the outer catheter having a second lumen for inflation of the balloon. The delivery device also includes a radiopaque marker band adjacent each end of the stent located at the distal end of the device adjacent a tapered tip. The device also includes a manifold having a flushing port fluidly coupled to an annular space between the inner and outer catheters and an inflation port fluidly coupled to the second lumen of the outer catheter for inflating the balloon.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a delivery system for delivering and deploying a stent to a treatment site within a vessel of the body of a living animal or living human. The delivery system of this invention includes a balloon catheter for dilating the vessel before deploying the stent and also after deploying the stent, if desired, without complete removal and insertion of separate catheters as was typically required in the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall view of a stent delivery apparatus useful in the practice of the present invention.

FIG. 2 is an enlarged view partly in section of detail 2 of FIG. 1.

FIG. 3 is a section view of a distal end of the apparatus of FIG. 1 showing inner and outer catheters, a stent in a radially inwardly collapsed condition and a balloon carried on the apparatus and in a deflated condition.

FIG. 4 is a section view taken alongline 4--4 of FIG. 3.

FIG. 5 is a perspective view of a portion of the apparatus of FIG. 3, but with the balloon inflated.

FIG. 6 is a view similar to FIG. 3, but with the outer catheter partially retracted and the stent partially deployed.

FIG. 7 is a view similar to that of FIG. 3, but with the stent fully deployed and with the outer catheter returned to the position shown in FIG. 3 and with the balloon inflated in post-deployment dilation.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures and most particularly to FIGS. 1, 2, and 3, a stent delivery system or medical device 10 may be seen. System or device 10 includes aninner catheter 12 having aproximal portion 14 and adistal portion 16. System 10 further has anouter catheter 20 having aproximal portion 22 and adistal portion 24. Theouter catheter 20 is disposed about theinner catheter 12 and forms anannular space 18 between at least thedistal portions 16 and 24 of the inner andouter catheters 12, 20. Device 10 also has adilation balloon 26 disposed about and secured by conventional means to thedistal portion 24 of the outer catheter, and device 10 further has astent 30 disposed in theannular space 18 between thedistal portion 24 of theouter catheter 20 and thedistal portion 16 of theinner catheter 12.

Device 10 also has a valve body ormanifold 32 secured (by conventional means) to theouter catheter 20. Manifold 32 has a throughlumen 34 aligned with the throughlumen 36 ofouter catheter 20.Inner catheter 12 is received inlumen 36. Aflushing port 38 is formed as part ofmanifold 32 and is in fluid communication withlumen 34, andannular space 18 when inner catheter is received in device 10. The flushingport 38 may be used to introduce a flushing or hydrophilic-coating-activating liquid (such as a saline solution), or to introduce a conventional lubricating liquid into theannular space 18 if desired. The flushing fluid is useful to eliminate air in theannular space 18, reducing the chance of air emboli therein. Valvebody 32 also preferably has aninflation port 40 in fluid communication with a auxiliary orsecond lumen 42 ofouter catheter 20. Referring now also to FIGS. 4 and 5, auxiliary orsecond lumen 42 is fluidly coupled to aninflation plenum 44 betweenballoon 26 andouter catheter 20 via askive 46. A guide wire (not shown) may be inserted inlumen 34 ofmanifold 32 to extend intolumen 28 ofinner catheter 12, and through atip 50, as desired.

Tip 50 of system 10 is preferably made of a soft elastomeric material to provide a relatively streamlined leading surface for the stent delivery system to ease insertion into the vessel. A pair ofradiopaque bands 52, 54 are preferably located at proximal and distal ends, respectively, of the stent as may be seen most clearly in FIG. 3.Bands 52 and 54 provide pronounced demarcation of the ends ofstent 30 to aid in the radiographically assisted or directed placement of thestent 30 in a vessel 60 as, for example, shown in phantom in FIGS. 6 and 7. The balloon may be axially configured withinbands 52 and 54 so that the bands provide an indication of the balloon location for the purpose of positioning the balloon at a desired dilatation site. In certain embodiments, a radiopaque band will define the proximal and/or distal end of the balloon.

Thestent 30 of the delivery system 10 is preferably a self-expanding type carried in a collapsed condition between theinner catheter 12 and theouter catheter 20. U.S. Pat. No. 4,655,771 B1, as re-examined, for a PROSTHESIS COMPRISING AN EXPANSIBLE OR CONTRACTILE TUBULAR BODY, naming Hans I. Wallsten as inventor, is hereby expressly incorporated by reference as an example of such a self-expanding prosthesis or stent.Balloon 26 is preferably located directly radially outwardly ofstent 30 exteriorly ofouter catheter 20. In use, the device 10 is preferably maneuvered to position thedistal portion 16 carryingstent 30 at a treatment site (typically using a radiographic techniques, either with or withoutbands 52 and 54) followed by inflating theballoon 26 to dilate the vessel 60 and thereafter deflating theballoon 26. Theballoon 26 is inflated or pressurized (typically by injecting saline solution via inflation port 40) using the separatesecond lumen 42 in theouter catheter 20. Next theouter catheter 20 is retracted (after theballoon 26 is deflated by extracting the saline solution via port 40) while the position of theinner catheter 12 is maintained such that thestent 30 is deployed at the treatment site. Alternatively, thedistal portion 16 may be positioned slightly distal of the treatment site to allow for slight proximal migration of thestent 30 during deployment. Theinner catheter 12 preferably has a radially outwardly directed stop means or element (which in the embodiment shown is combined in function with radiopaque band 52) located adjacent a proximal end of thestent 30 to restrain axial movement of thestent 30 as theouter catheter 20 is retracted in deploying thestent 30. Finally, the device 10 is withdrawn from the vessel or canal 60 either with or without returning theouter catheter 20 distally towardstip 50. It is to be understood that pre-deployment inflation ofballoon 26 may be omitted, if desired. Furthermore,outer catheter 20 may be moved to positionballoon 26 radially interiorly ofstent 30 and inflated after deployment ofstent 30 as shown in FIG. 7, if desired.Balloon 26 is thereafter deflated and device 10 withdrawn from vessel 60.

It may thus be seen that the present invention includes a method of using the combined stent and delivery device to both dilate a partially occluded portion of a body canal and deploy a stent therein without the necessity of removing the device between those two operations where the operations include dilating a partial occluded portion of a body canal using a balloon carried on a distal portion of the device and the further operation of retracting an outer sleeve or catheter overlying a self-expanding stent such that the stent is released in the dilated portion of the body canal. According to one aspect of the method of the present invention, in certain procedures the distal region of the delivery device may be preferably located slightly distal of the treatment site prior to stent deployment so that the stent will be deployed at the desired location with respect to the treatment site. This will allow for the known propensity of certain self-expanding stents to migrate slightly proximally during deployment in certain situations.

More particularly, the method includes inserting the stent delivery device 10 into the vessel 60 wherein the device has a self-expandingstent 30 carried in a collapsed condition between the inner andouter catheters 12, 20 and restrained against proximal axial movement by a step orelement 52 and the device 10 further has adilation balloon 26 carried thereon, all at a distal region of the device 10. The method also includes manoeuvering the device 10 to position thestent 30 at a treatment site, typically a partially occluded portion of the vessel 60, whereupon theouter catheter 20 is retracted such that thestent 30 is deployed at the treatment site, and the device 10 is thereafter withdrawn from the vessel 60. Further aspects of the method of the present invention include the additional steps of positioning theballoon 26 at the treatment site, inflating theballoon 26 to dilate the vessel 60, and deflating theballoon 26, all after manoeuvering the device 10 to position thestent 30 at the treatment site and before deploying thestent 30. Still further (optional) aspects of the method of the present invention include the additional steps of advancing theouter catheter 20 distally to position theballoon 26 interiorly (or radially inwardly) of thestent 30 at the treatment site, inflating theballoon 26 within the stent 30 (to further expand or "set" the stent 30) and thereafter deflating theballoon 26, in this case all after deploying thestent 30 and before withdrawing the device 10 from the vessel 60. Of course, it is to be understood that both pre- and post-deployment balloon inflation or vessel dilation may be utilized in the practice of the present invention.

The invention is not to be taken as limited to all of the details thereof as modifications and variations thereof may be made without departing from the spirit or scope of the invention.

Claims (15)

What is claimed is:

1. A medical device comprising:

a) an inner catheter having a proximal portion and a distal portion;

b) an outer catheter having a first lumen therethrough and a proximal portion and a distal portion, the outer catheter disposed around the inner catheter and forming an annular space between the distal portion of the outer catheter and the distal portion of the inner catheter;

c) a dilation balloon disposed around the distal portion of the outer catheter; and

d) a stent disposed in the annular space between the distal portion of the outer catheter and the distal portion of the inner catheter; and

e) a manifold having

i) a flushing port fluidly coupled to the annular space between the inner catheter and first lumen of the outer catheter, and

ii) an inflation port fluidly coupled to a second lumen in the outer catheter to permit inflation of the balloon.

2. The device of claim 1 wherein the inner catheter further comprises a radially outwardly directed element adjacent a proximal end of the stent to restrain axial movement of the stent as the outer catheter is retracted.

3. The device of claim 2 wherein the element comprises a first radiopaque band.

4. The device of claim 3 further comprising a second radiopaque band adjacent a distal end of the stent.

5. The device of claim 1 wherein the stent is a self-expanding stent.

6. The device of claim 5 wherein the annular space between the inner and outer catheters is sized to retain the stent in a radially collapsed condition.

7. The device of claim 1 wherein the manifold further comprises:

iii) a through lumen for permitting passage of a guide wire therethrough.

8. A stent delivery system comprising:

a) an inner catheter having a proximal portion and a distal portion, the inner catheter forming a lumen at least in its distal portion;

b) an outer catheter disposed around the inner catheter and forming an annular space between the inner and outer catheters, the outer catheter having a dilation balloon disposed around a distal region thereof, and a lumen fluidly coupled to the interior of the dilation balloon; and

c) a stent located at a distal region of the annular space between the inner and outer catheters,

wherein the balloon is positioned radially outwardly of the stent and further wherein the balloon is inflatable for pre-stent-deployment dilation of a vessel containing the device.

9. The stent delivery system of claim 8 wherein the inner catheter further comprises a tapered tip at an end of the distal portion thereof.

10. The stent delivery system of claim 8 wherein the stent is releasable from the annular space between the inner and outer catheters by retraction of the outer catheter away from the distal end of the inner catheter.

11. A medical device comprising:

a) an inner catheter having a proximal portion and a distal portion;

b) an outer catheter having a first lumen therethrough and a proximal portion and a distal portion, the outer catheter disposed around the inner catheter and forming an annular space between the distal portion of the outer catheter and the distal portion of the inner catheter;

c) a dilation balloon disposed around the distal portion of the outer catheter; and

d) a stent disposed in the annular space between the distal portion of the outer catheter and the distal portion of the inner catheter

wherein the dilation balloon is positioned radially outwardly of the stent and further wherein the balloon is inflatable for pre-stent-deployment dilation of a vessel containing the device.

12. A stent delivery system comprising:

a) an inner catheter having a proximal portion and a distal portion, the inner catheter forming a lumen at least in its distal portion;

b) an outer catheter disposed around the inner catheter and forming an annular space between the inner and outer catheters, the outer catheter having a dilation balloon disposed around a distal region thereof, and a lumen fluidly coupled to the interior of the dilation balloon; and

c) a stent located at a distal region of the annular space between the inner and outer catheters

d) a manifold having

i) a flushing port fluidly coupled to the annular space between the inner catheter and first lumen of the outer catheter, and

ii) an inflation port fluidly coupled to a second lumen in the outer catheter to permit inflation of the balloon.

13. The stent delivery system of claim 12 wherein the inner catheter further comprises a tapered tip at an end of the distal portion thereof.

14. The stent delivery system of claim 12 wherein the stent is releasable from the annular space between the inner and outer catheters by retraction of the outer catheter away from the distal end of the inner catheter.

15. The device of claim 12 wherein the manifold further comprises:

iii) a through lumen for permitting passage of a guide wire therethrough.

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